But shortly after the awww heard round the world, what immediately sprang to mind was Princess Diana and Prince Charles showing off their firstborn son more than 30 years ago.

And now here are both, side by side!

Tim Graham/Getty Images

While Kate held the sweetly swaddled George in their new pics, William sat on his father's lap and both his mum and dad leaned in for some snuggling in the decades-old image seen here. (And surely if online shopping had existed then, Diana's ruffly blouse would have sold out within hours, just like Kate's fuchsia Séraphine maternity dress.)

The stuffed koala-clutching Will is obviously some months older in his pic, taken at Kensington Palace back when the future Duke of Cambridge was still an only child.

But his son, in his unofficial-yet-momentous family portrait snapped this month by his granddad Michael Middleton outside their home in Bucklebury, is already sporting a royal visage for the ages as well.

TRH The Duke and Duchess of Cambridge

"I think the last few weeks for me have been just a very different emotional experience, something I never thought I would feel myself," William told CNN's Max Foster in his first sit-down interview since becoming a father, part of a one-hour documentary about the Duke of Cambridge airing Sept. 16. "And I find, again it's only been a short period, but a lot of things affect me differently now."

He called his son "a little bit of a rascal," comparing him to both his younger self and that of his brother, Prince Harry.

"As any new parent knows," Will added, "you're only too happy to show off your new child and, you know, proclaim that he is the best-looking or the best everything."

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